A frame for a core of a distribution transformer serves the purpose of clamping and compressing top and bottom yokes of the core, thereby holding the core together. The construction of a conventional transformer core frame typically involves bolting, welding, or dowel pinning to achieve mechanical interlocking of component members of the core frame. The production of such core frames is costly and labor intensive. Accordingly, there is a need for a new type of core frame that is simpler and easier to produce. The present invention is directed to such an improved core frame.